The present invention relates to a plasma or gas discharge display for displaying light phenomena, and in particular relates to an improved enclosure or envelope for containing the display, and other improved features relating to the power supply for such a display device.
Lamps and lighting arrangements which utilize discharges in gas filled vessels have, of course, been known for a long time. Nikoli Tesla performed experiments in the early 1900's with the application of high voltage, high frequency signals to produce discharges in gases. And of course, neon signs and fluorescent lights are two common examples of applications of electrically generated gaseous discharges.
One particularly interesting aspect of electrically induced gaseous discharges has been in the area of utilizing such discharges as an art form. In particular, there have been various devices on the market and shown at shows which utilize a transparent globe or sphere enclosing an ionizable gas mixture. High voltage, high frequency signals are applied to the globe through one or more electrodes to induce visually interesting electrical discharges in the gas contained within the globe or sphere towards an external ground. Such globes are made of a transparent dielectric material, such as glass, and the globes can function to capacitively couple a conductor on the outside of the globe, such as a human hand, to the "conductive" gas on the inside of the globe or sphere. Thus, as an art form, placing one's hand in contact with or adjacent to a globe or sphere influences and affects the discharge taking place within the sphere, leading to interesting visual effects and control over those effects.
Prior art patents exist on gas discharge or plasma spheres as art forms, including U.S. Pat. Nos. 4,379,253 and 4,754,199. Concerns attendant to any such sphere construction are safely coupling as much power as possible into the sphere, so as to produce a more intense visible display, and producing as interesting a visual pattern as possible.